Chip package structure and method for forming the same

ABSTRACT

A method for forming a chip package structure is provided. The method includes forming a dielectric layer over a redistribution structure. The redistribution structure includes a dielectric structure and a plurality of wiring layers in or over the dielectric structure. The method includes forming a first conductive bump structure and a shield bump structure over the dielectric layer. The first conductive bump structure is electrically connected to the wiring layers, and the shield bump structure is electrically insulated from the wiring layers. The method includes bonding a first chip structure to the redistribution structure through the first conductive bump structure. The first chip structure is electrically insulated from the shield bump structure, and the first chip structure extends across a first sidewall of the shield bump structure.

BACKGROUND

Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating layers or dielectric layers, conductive layers, and semiconductor layers over a semiconductor substrate, and patterning the various material layers using photolithography processes and etching processes to form circuit components and elements thereon.

Many integrated circuits (IC) are typically manufactured on a semiconductor wafer. Technological advances in IC materials and design have produced generations of ICs. Each generation has smaller and more complex circuits than the previous generation. The dies of the wafer may be processed and packaged at the wafer level, and various technologies have been developed for wafer level packaging. Since the chip package structure may need to include multiple chips with multiple functions, it is a challenge to form a reliable chip package structure with multiple chips.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It should be noted that, in accordance with standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

FIGS. 1A-1I are cross-sectional views of various stages of a process for forming a chip package structure, in accordance with some embodiments.

FIG. 1B-1 is a top view of the shield pad of FIG. 1B, in accordance with some embodiments.

FIG. 1E-1 is a top view of the chip package structure of FIG. 1E, in accordance with some embodiments.

FIG. 1F-1 is a top view of the chip package structure of FIG. 1F, in accordance with some embodiments.

FIG. 1F-2 is a cross-sectional view of the chip structure of FIG. 1F, in accordance with some embodiments.

FIG. 1I-1 is a top view of the chip package structure of FIG. 1I, in accordance with some embodiments.

FIG. 2 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 3 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 4 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 5 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 6 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 7 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 8 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 9 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 10 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 11 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 12 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 13 is a top view of a chip package structure, in accordance with some embodiments.

FIG. 14 is a top view of a chip package structure, in accordance with some embodiments.

FIGS. 15A-15C are cross-sectional views of various stages of a process for forming a chip package structure, in accordance with some embodiments.

FIGS. 16A-16C are cross-sectional views of various stages of a process for forming a chip package structure, in accordance with some embodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, or examples, for implementing different features of the subject matter provided. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Furthermore, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.

The term “substantially” in the description, such as in “substantially flat” or in “substantially coplanar”, etc., will be understood by the person skilled in the art. In some embodiments the adjective substantially may be removed. Where applicable, the term “substantially” may also include embodiments with “entirely”, “completely”, “all”, etc. The term “substantially” may be varied in different technologies and be in the deviation range understood by the skilled in the art. For example, the term “substantially” may also relate to 90% of what is specified or higher, such as 95% of what is specified or higher, especially 99% of what is specified or higher, including 100% of what is specified, though the present invention is not limited thereto. Furthermore, terms such as “substantially parallel” or “substantially perpendicular” may be interpreted as not to exclude insignificant deviation from the specified arrangement and may include for example deviations of up to 10°. The word “substantially” does not exclude “completely” e.g. a composition which is “substantially free” from Y may be completely free from Y.

The term “about” may be varied in different technologies and be in the deviation range understood by the skilled in the art. The term “about” in conjunction with a specific distance or size is to be interpreted so as not to exclude insignificant deviation from the specified distance or size. For example, the term “about” may include deviations of up to 10% of what is specified, though the present invention is not limited thereto. The term “about” in relation to a numerical value x may mean x±5 or 10% of what is specified, though the present invention is not limited thereto.

Some embodiments of the disclosure are described. Additional operations can be provided before, during, and/or after the stages described in these embodiments. Some of the stages that are described can be replaced or eliminated for different embodiments. Additional features can be added to the semiconductor device structure. Some of the features described below can be replaced or eliminated for different embodiments. Although some embodiments are discussed with operations performed in a particular order, these operations may be performed in another logical order.

As shown in FIG. 1A, a carrier substrate 10 is provided, in accordance with some embodiments. The carrier substrate 10 is made of glass, silicon, metal or another suitable material, in accordance with some embodiments. As shown in FIG. 1A, a dielectric layer 111 is formed over the carrier substrate 10, in accordance with some embodiments.

The dielectric layer 111 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The dielectric layer 111 is formed using a deposition process (e.g. a chemical vapor deposition process or a physical vapor deposition process), a photolithography process, and an etching process, in accordance with some embodiments.

As shown in FIG. 1A, bonding pads 112 and a wiring layer 113 are respectively formed in and over the dielectric layer 111, in accordance with some embodiments. The bonding pads 112 and the wiring layer 113 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments.

As shown in FIG. 1A, a dielectric layer 114 is formed over the wiring layer 113 and the dielectric layer 111, in accordance with some embodiments. The dielectric layer 114 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The dielectric layer 114 is formed using a deposition process (e.g. a chemical vapor deposition process or a physical vapor deposition process), a photolithography process, and an etching process, in accordance with some embodiments.

As shown in FIG. 1A, conductive vias 115 and a wiring layer 116 are respectively formed in and over the dielectric layer 114, in accordance with some embodiments. The conductive vias 115 and the wiring layer 116 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments.

As shown in FIG. 1A, a dielectric layer 117 is formed over the wiring layer 116 and the dielectric layer 114, in accordance with some embodiments. The dielectric layer 117 has openings 117 a, in accordance with some embodiments. The openings 117 a expose the wiring layer 116 thereunder, in accordance with some embodiments.

The dielectric layer 117 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The dielectric layer 117 is formed using a deposition process (e.g. a chemical vapor deposition process or a physical vapor deposition process), a photolithography process, and an etching process, in accordance with some embodiments.

As shown in FIG. 1A, a seed layer 118 a is conformally formed over the dielectric layer 117 and the exposed wiring layer 116, in accordance with some embodiments. The seed layer 118 a is made of a conductive material, such as metal (e.g., copper, aluminum, gold, silver, or tungsten) or alloys thereof, in accordance with some embodiments. The seed layer 118 a is formed using a deposition process, such as a physical vapor deposition process or a chemical vapor deposition process, in accordance with some embodiments.

As shown in FIG. 1A, a mask layer M1 is formed over the seed layer 118 a, in accordance with some embodiments. The mask layer M1 has openings OP1 and OP2 exposing the seed layer 118 a thereunder, in accordance with some embodiments. The mask layer M1 is made of a polymer material, such as a photoresist material, in accordance with some embodiments.

As shown in FIG. 1A, a conductive layer 118 b is formed in the openings OP1 and OP2 and over the seed layer 118 a, in accordance with some embodiments. The conductive layer 118 b is made of a conductive material, such as metal (e.g., copper, aluminum, gold, silver, or tungsten) or alloys thereof, in accordance with some embodiments. The conductive layer 118 b is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 1B, the mask layer M1 and the seed layer 118 a under the mask layer M1 are removed, in accordance with some embodiments. The conductive layer 118 b in the openings 117 a and the seed layer 118 a thereunder together form conductive vias 118 c, in accordance with some embodiments.

The conductive layer 118 b over the dielectric layer 117 and originally in the openings OP1 and the seed layer 118 a thereunder together form a wiring layer 118 d, in accordance with some embodiments. The wiring layer 118 d is a topmost one of the wiring layers 113, 116 and 118 d, in accordance with some embodiments.

The conductive layer 118 b over the dielectric layer 117 and originally in the openings OP2 and the seed layer 118 a thereunder together form a shield pad 118′, in accordance with some embodiments. The shield pad 118′ and the wiring layer 118 d are made of a same material, in accordance with some embodiments. The shield pad 118′ is electrically insulated from the wiring layers 113, 116 and 118 d, in accordance with some embodiments.

FIG. 1B-1 is a top view of the shield pad of FIG. 1B, in accordance with some embodiments. FIG. 1B shows a cross-sectional view of the shield pad 118′ along a sectional line 1B-1B′ in FIG. 1B-1 , in accordance with some embodiments. As shown in FIGS. 1B and 1B-1 , the shield pad 118′ has a mesh shape, in accordance with some embodiments. The shield pad 118′ has holes 118 h, in accordance with some embodiments. The holes 118 h are through holes, in accordance with some embodiments. In some embodiments, the holes 118 h are arranged in an array. In some other embodiments, the holes 118 h are arranged randomly.

As shown in FIGS. 1B and 1B-1 , a ratio of a top surface area of the conductive layer 118 b to the total area of the shield pad 118′, including the top surface area of the conductive layer 118 b and the total area of the holes 118 h, is greater than about 0.5, in accordance with some embodiments. If the ratio is less than about 0.5, the stress shielding ability of the shield pad 118′ is not enough to protect the wires thereunder, in accordance with some embodiments. In some embodiments, the ratio ranges from about 0.7 to about 1.

The holes 118 h are also referred to as outgassing holes, in accordance with some embodiments. The holes 118 h are able to permit outgassing of the dielectric layer 117, which prevents the shield pad 118′ from being damaged by outgassing phenomena, in accordance with some embodiments. Therefore, the holes 118 h improve the reliability of the shield pad 118′, in accordance with some embodiments. In this step, a redistribution structure 210 is substantially formed, in accordance with some embodiments.

As shown in FIG. 1C, a dielectric layer 119 is formed over the dielectric layer 117, the wiring layer 118 d, and the shield pad 118′, in accordance with some embodiments. The dielectric layer 119 is used to be a stress buffer layer, in accordance with some embodiments. The dielectric layer 119 has openings 119 a, in accordance with some embodiments. The openings 119 a expose the wiring layer 118 d thereunder, in accordance with some embodiments.

The dielectric layer 119 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The dielectric layer 119 is formed using a deposition process (e.g. a chemical vapor deposition process or a physical vapor deposition process), a photolithography process, and an etching process, in accordance with some embodiments.

As shown in FIG. 1C, a seed layer 211 is conformally formed over the dielectric layer 119 and the exposed wiring layer 118 d, in accordance with some embodiments. The seed layer 211 is made of a conductive material, such as metal (e.g., copper, aluminum, gold, silver, or tungsten) or alloys thereof, in accordance with some embodiments. The seed layer 211 is formed using a deposition process, such as a physical vapor deposition process or a chemical vapor deposition process, in accordance with some embodiments.

As shown in FIG. 1C, a mask layer 212 is formed over the seed layer 211, in accordance with some embodiments. The mask layer 212 has openings 212 a and 212 b exposing the seed layer 211 thereunder, in accordance with some embodiments. The mask layer 212 is made of a polymer material, such as a photoresist material, in accordance with some embodiments.

As shown in FIG. 1C, an under bump metallization layer 213 is formed in the openings 212 a and 212 b and over the seed layer 211, in accordance with some embodiments. The under bump metallization layer 213 is made of a conductive material, such as metal (e.g., titanium, copper, and/or nickel) or alloys thereof (e.g. titanium copper), in accordance with some embodiments. The under bump metallization layer 213 is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 1C, a barrier layer 214 is formed in the openings 212 a and 212 b and over the under bump metallization layer 213, in accordance with some embodiments. The barrier layer 214 is used to prevent the material of bumps subsequently formed over the barrier layer 214 from diffusing into the under bump metallization layer 213, in accordance with some embodiments. The barrier layer 214 is made of a conductive material, such as metal (e.g., tantalum) or nitrides (e.g. titanium nitride and/or tantalum nitride), in accordance with some embodiments. The barrier layer 214 is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 1C, a conductive layer 215 is formed in the openings 212 a and 212 b and over the barrier layer 214, in accordance with some embodiments. The conductive layer 215 in the openings 212 a form conductive bumps 215 a, in accordance with some embodiments. The conductive layer 215 in the openings 212 b form a shield bump 215 b, in accordance with some embodiments.

The conductive layer 215 is made of a conductive material, such as metal (e.g., titanium, copper, nickel, or aluminum) or alloys thereof, in accordance with some embodiments. The conductive layer 215 is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 1D, a mask layer 216 is formed over the mask layer 212 and the shield bump 215 b, in accordance with some embodiments. The mask layer 216 has openings 216 a over the openings 212 a and exposing the conductive bumps 215 a, in accordance with some embodiments. The mask layer 216 is made of a polymer material, such as a photoresist material, in accordance with some embodiments.

As shown in FIG. 1D, a solder layer 217 a is formed in the openings 216 a and over the conductive bumps 215 a, in accordance with some embodiments. The solder layer 217 a is made of a conductive material, such as a tin-based alloy, in accordance with some embodiments. The solder layer 217 a is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 1E, the mask layers 212 and 216 and the seed layer 211 under the mask layer 212 are removed, in accordance with some embodiments. Each conductive bump 215 a, the barrier layer 214 thereunder, the under bump metallization layer 213 thereunder, and the seed layer 211 thereunder together form a conductive bump structure 218, in accordance with some embodiments. The conductive bump structures 218 are electrically connected to the wiring layers 113, 116, and 118 d, in accordance with some embodiments. As shown in FIG. 1E, the solder layer 217 a is reflowed to form solder bumps 217 over the conductive bump structures 218, in accordance with some embodiments.

The shield bump 215 b, the barrier layer 214 thereunder, the under bump metallization layer 213 thereunder, and the seed layer 211 thereunder together form a shield bump structure 219, in accordance with some embodiments. The shield bump structure 219 is electrically insulated from the wiring layers 113, 116, and 118 d, in accordance with some embodiments.

The shield bump structure 219 is thicker than the shield pad 118′, in accordance with some embodiments. That is, the thickness T1 of the shield bump structure 219 is greater than the thickness T2 of the shield pad 118′, in accordance with some embodiments. The shield bump structure 219 is thicker than each wiring layer 113, 116, or 118 d, in accordance with some embodiments.

FIG. 1E-1 is a top view of the chip package structure of FIG. 1E, in accordance with some embodiments. FIG. 1E is a cross-sectional view illustrating the chip package structure along a sectional line 1E-1E′ in FIG. 1E-1 , in accordance with some embodiments. As shown in FIGS. 1E and 1E-1 , the shield bump structure 219 partially overlaps the shield pad 118′, in accordance with some embodiments. As shown in FIGS. 1E and 1E-1 , the shield bump structure 219 has holes 219 a exposing the dielectric layer 119 thereunder, in accordance with some embodiments. The shield bump structure 219 has opposite sidewalls 219 b and 219 c, in accordance with some embodiments.

The shield pad 118′ has opposite sidewalls 118 f and 118 g, in accordance with some embodiments. The sidewall 219 b is misaligned with the sidewall 118 f in an axis Y perpendicular to a top surface 119 b of the dielectric layer 119, in accordance with some embodiments. The sidewall 219 c is misaligned with the sidewall 118 g in the axis Y, in accordance with some embodiments.

As shown in FIG. 1E-1 , the sidewall 219 b is spaced apart from the sidewall 118 f by as distance D1, in accordance with some embodiments. The sidewall 219 c is spaced apart from the sidewall 118 g by as distance D2, in accordance with some embodiments. The distance D1 or D2 ranges from about 5 μm to about 50 μm, in accordance with some embodiments. As shown in FIG. 1E-1 , the holes 219 a of the shield bump structure 219 are misaligned with the holes 118 h of the shield pad 118′, in accordance with some embodiments.

Since the misalignment design may increase the stress transmitting path length from an edge of a chip structure subsequently formed to the wiring layers under the shield pad 118′, the misalignment design may improve the stress shielding ability of the shield bump structure 219 and the shield pad 118′. Therefore, the reliability of the chip package structure with the shield bump structure 219 and the shield pad 118′ is improved, in accordance with some embodiments.

FIG. 1F-1 is a top view of the chip package structure of FIG. 1F, in accordance with some embodiments. FIG. 1F is a cross-sectional view illustrating the chip package structure along a sectional line 1F-1F′ in FIG. 1F-1 , in accordance with some embodiments. As shown in FIGS. 1F and 1F-1 , chip structures 220A and 220B are bonded to the solder bumps 217, in accordance with some embodiments. The chip structures 220A and 220B are electrically connected to the wiring layer 118 d through the solder bumps 217 and the conductive bump structures 218, in accordance with some embodiments.

The chip structures 220A and 220B are electrically insulated from the shield bump structure 219 and the shield pad 118′, in accordance with some embodiments. The chip structure 220A extends across the sidewall 219 b of the shield bump structure 219 and the sidewall 118 f of the shield pad 118′, in accordance with some embodiments. The chip structure 220B extends across the sidewall 219 c of the shield bump structure 219 and the sidewall 118 g of the shield pad 118′, in accordance with some embodiments.

The chip structure 220A is spaced apart from the chip structure 220B by a gap G1, in accordance with some embodiments. The gap G1 is over the shield bump structure 219 and the shield pad 118′, in accordance with some embodiments. The shield bump structure 219 is wider than the gap G1, in accordance with some embodiments. The shield bump structure 219 extends across the gap G1, in accordance with some embodiments. The shield pad 118′ extends across the gap G1, in accordance with some embodiments.

In some embodiments, as shown in FIG. 1F, a wire 116 a of the wiring layer 116 extends across the gap G1, and the shield bump structure 219 and the shield pad 118′ are both over the wire 116 a under the gap G1. The wire 116 a extends across sidewalls 222 a of the chip structures 220A and 220B, and the shield bump structure 219 and the shield pad 118′ cover the portions of the wire 116 a under the sidewalls 222 a, in accordance with some embodiments.

The chip structures 220A and 220B partially overlap the shield bump structure 219 and the shield pad 118′, in accordance with some embodiments. In some embodiments, a portion of the shield bump structure 219 is between the chip structure 220A and the shield pad 118′. In some embodiments, another portion of the shield bump structure 219 is between the chip structure 220B and the shield pad 118′.

The chip structure 220A includes a chip-containing structure 222A and conductive bump structures 224 connected to the chip-containing structure 222A, in accordance with some embodiments. The chip structure 220B includes a chip-containing structure 222B and conductive bump structures 224 connected to the chip-containing structure 222B, in accordance with some embodiments.

The chip-containing structure 222A or 222B includes a chip or a package with at least one chip, in accordance with some embodiments. For example, as shown in FIG. 1F-2 , the chip-containing structure 222A includes a package including a wiring substrate 225, a chip 226, conductive pillars 227, an underfill layer 228, and a molding layer 229, in accordance with some embodiments. The chip 226 is bonded to the wiring substrate 225 through the conductive pillars 227, in accordance with some embodiments.

The underfill layer 228 is filled between the chip 226 and the wiring substrate 225, in accordance with some embodiments. The molding layer 229 is over the wiring substrate 225, the chip 226, and the underfill layer 228, in accordance with some embodiments. The chip 226 is made of, for example, a semiconductor material.

The conductive pillars 227 are made of a conductive material, in accordance with some embodiments. The underfill layer 228 and the molding layer 229 are made of different insulating materials, in accordance with some embodiments. Similarly, the chip-containing structure 222B may include a package similar to or the same as the package of 1F-2.

Each conductive bump structure 224 includes an under bump metallization layer 224 a, a barrier layer 224 b, and a conductive bump 224 c, in accordance with some embodiments. The under bump metallization layer 224 a is made of a conductive material, such as metal (e.g., titanium, copper, and/or nickel) or alloys thereof (e.g. titanium copper), in accordance with some embodiments. The barrier layer 224 b is made of a conductive material, such as metal (e.g., tantalum) or nitrides (e.g. titanium nitride and/or tantalum nitride), in accordance with some embodiments. The conductive bump 224 c is made of a conductive material, such as metal (e.g., titanium, copper, nickel, or aluminum) or alloys thereof, in accordance with some embodiments.

In some embodiments, a portion of the shield bump structure 219 under the chip structure 220A has a width W1. In some embodiments, a portion of the shield bump structure 219 under the chip structure 220B has a width W2. The width W1 or W2 ranges from about 60 μm to about 150 μm, in accordance with some embodiments.

In some embodiments, a ratio of the width W1 to a distance D3 between the conductive bump structure 224 and the sidewall 222 a of the chip-containing structure 222A ranges from about 0.5 to less than about 1. In some embodiments, a ratio of the width W2 to a distance D4 between the conductive bump structure 224 and the sidewall 222 a of the chip-containing structure 222B ranges from about 0.5 to less than about 1. If the ratio is less than about 0.5, the stress shielding ability of the shield bump structure 219 is not enough to protect the wires thereunder, in accordance with some embodiments.

As shown in FIG. 1G, an underfill layer 230 is formed between the chip structures 220A and 220B and the redistribution structure 210, in accordance with some embodiments. The underfill layer 230 surrounds the chip structures 220A and 220B, the solder bumps 217, the conductive bump structures 218, and the shield bump structure 219, in accordance with some embodiments.

The underfill layer 230 extends into the gap G1 between the chip structures 220A and 220B, in accordance with some embodiments. The gap G1 is filled with the underfill layer 230, in accordance with some embodiments. The underfill layer 230 is made of an insulating material, such as a polymer material, in accordance with some embodiments.

As shown in FIG. 1G, the molding layer 240 is formed over the redistribution structure 210 and the underfill layer 230, in accordance with some embodiments. The molding layer 240 surrounds the chip structures 220A and 220B and the underfill layer 230, in accordance with some embodiments. The molding layer 240 is made of an insulating material, such as a polymer material (e.g., epoxy), in accordance with some embodiments.

As shown in FIG. 1H, the carrier substrate 10 is removed, in accordance with some embodiments. As shown in FIG. 1H, bumps 250 are formed over the bonding pads 112, in accordance with some embodiments. The bumps 250 are made of a conductive material, such as a tin-based alloy, in accordance with some embodiments. The bumps 250 are formed using a plating process, such as an electroplating process, and a reflow process, in accordance with some embodiments.

As shown in FIG. 1H, a cutting process is performed to cut the redistribution structure 210, the dielectric layer 119, and the molding layer 240 along the cutting lines C to form chip package structures P, in accordance with some embodiments. The process of FIGS. 1A-1H is a wafer level packaging process, in accordance with some embodiments. For the sake of simplicity, FIGS. 1A-1H only show the structure for forming one of the chip package structures P, in accordance with some embodiments.

As shown in FIG. 1I, a wiring substrate 260 is provided, in accordance with some embodiments. The wiring substrate 260 includes a dielectric layer 261, wiring layers 262, conductive vias 263 and 264, and bonding pads 265, in accordance with some embodiments. The bonding pads 265 are formed over the dielectric layer 261, in accordance with some embodiments. The wiring layers 262 and the conductive vias 263 and 264 are formed in the dielectric layer 261, in accordance with some embodiments.

The conductive vias 263 are electrically connected between different wiring layers 262, in accordance with some embodiments. The conductive vias 264 are electrically connected between the wiring layer 262 and the bonding pads 265, in accordance with some embodiments. For the sake of simplicity, FIG. 1I only shows two of the wiring layers 262, in accordance with some embodiments.

The dielectric layer 261 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The dielectric layer 261 is formed using deposition processes (e.g. chemical vapor deposition processes or physical vapor deposition processes), photolithography processes, and etching processes, in accordance with some embodiments.

The wiring layers 262 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments. The conductive vias 263 and 264 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments. The bonding pads 265 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments.

In some embodiments, the wiring layers 262, the conductive vias 263 and 264, and the bonding pads 265 are made of the same material. In some other embodiments. the wiring layers 262, the conductive vias 263 and 264, and the bonding pads 265 are made of different materials.

FIG. 1I-1 is a top view of the chip package structure of FIG. 1I, in accordance with some embodiments. FIG. 1I is a cross-sectional view illustrating the chip package structure along a sectional line 1I-1I′ in FIG. 1I-1 , in accordance with some embodiments. As shown in FIGS. 1I and 1I-1 , the chip package structure P is bonded to the wiring substrate 260 through the bumps 250, in accordance with some embodiments. The bumps 250 are connected between the bonding pads 112 and 265, in accordance with some embodiments. The shield pad 118′ and the shield bump structure 219 are electrically insulated from the wiring substrate 260, in accordance with some embodiments. In this step, a chip package structure 100 is substantially formed, in accordance with some embodiments.

The thermal expansion coefficient of the chip structures 220A and 220B is different from (e.g., less than) that of the wiring substrate 260, in accordance with some embodiments. The mismatch of thermal expansion coefficients between the chip structures 220A and 220B and the wiring substrate 260 may induce a thermal stress in the redistribution structure 210, especially in the portion of the redistribution structure 210 under the gap G1 or the sidewalls 222 a, in accordance with some embodiments. The thermal stress tends to result in cracks in the wires extending across the gap G1 or the sidewalls 222 a, in accordance with some embodiments. Since the stress is concentrated in the gap G1 or on the sidewalls 222 a, the shield bump structure 219 and the shield pad 118′ are able to shield the stress to protect the wires thereunder, in accordance with some embodiments. Therefore, the shield bump structure 219 and the shield pad 118′ improve the reliability of the chip package structure 100, in accordance with some embodiments.

FIG. 2 is a top view of a chip package structure 200, in accordance with some embodiments. For the sake of simplicity, FIG. 2 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 2 , the chip package structure 200 is similar to the chip package structure 100 of FIG. 1I-1 , except that the shield bump structure 219 and the shield pad 118′ of the chip package structure 200 are further under the sidewalls 222 b, 222 c, and 222 d of the chip structures 220A and 220B, in accordance with some embodiments.

FIG. 3 is a top view of a chip package structure 300, in accordance with some embodiments. For the sake of simplicity, FIG. 3 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 3 , the chip package structure 300 is similar to the chip package structure 200 of FIG. 2 , except that the chip package structure 300 only has the chip structure 220A and does not have the chip structure 220B, in accordance with some embodiments.

FIG. 4 is a top view of a chip package structure 400, in accordance with some embodiments. For the sake of simplicity, FIG. 4 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 4 , the chip package structure 400 is similar to the chip package structure 100 of FIG. 1I-1 , except that the shield bump structure 219 and the shield pad 118′ of the chip package structure 400 have a rectangular shape, in accordance with some embodiments.

FIG. 5 is a top view of a chip package structure 500, in accordance with some embodiments. For the sake of simplicity, FIG. 5 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 5 , the chip package structure 500 is similar to the chip package structure 100 of FIG. 1I-1 , except that the shield bump structure 219 and the shield pad 118′ of the chip package structure 500 have a round shape, in accordance with some embodiments.

FIG. 6 is a top view of a chip package structure 600, in accordance with some embodiments. For the sake of simplicity, FIG. 6 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 6 , the chip package structure 600 is similar to the chip package structure 500 of FIG. 5 , except that the shield bump structure 219 has holes 219 a, in accordance with some embodiments.

For the sake of simplicity, FIG. 6 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 7 is a top view of a chip package structure 700, in accordance with some embodiments. For the sake of simplicity, FIG. 7 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 7 , the chip package structure 700 is similar to the chip package structure 100 of FIG. 1I-1 , except that the shield bump structure 219 and the shield pad 118′ of the chip package structure 700 have an oval-like shape, in accordance with some embodiments.

FIG. 8 is a top view of a chip package structure 800, in accordance with some embodiments. For the sake of simplicity, FIG. 8 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 8 , the chip package structure 800 is similar to the chip package structure 700 of FIG. 7 , except that the shield bump structure 219 of the chip package structure 800 have portions 219P spaced apart from each other, in accordance with some embodiments. The portions 219P have an oval-like shape, in accordance with some embodiments. The portions 219P have holes 219 a, in accordance with some embodiments.

For the sake of simplicity, FIG. 8 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 9 is a top view of a chip package structure 900, in accordance with some embodiments. For the sake of simplicity, FIG. 9 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 9 , the chip package structure 900 is similar to the chip package structure 400 of FIG. 4 , except that the shield bump structure 219 of the chip package structure 900 have a main portion 219 m and extending portions 219 e connected to the main portion 219 m, in accordance with some embodiments. The extending portions 219 e are under the chip-containing structures 222A and 222B, in accordance with some embodiments. The main portion 219 m and the extending portions 219 e have a rectangular shape, in accordance with some embodiments.

For the sake of simplicity, FIG. 9 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 10 is a top view of a chip package structure 1000, in accordance with some embodiments. For the sake of simplicity, FIG. 10 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 10 , the chip package structure 1000 is similar to the chip package structure 900 of FIG. 9 , except that the shield bump structure 219 of the chip package structure 1000 have holes 219 a, in accordance with some embodiments.

For the sake of simplicity, FIG. 10 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 11 is a top view of a chip package structure 1100, in accordance with some embodiments. For the sake of simplicity, FIG. 11 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 11 , the chip package structure 1100 is similar to the chip package structure 400 of FIG. 4 , except that the shield bump structure 219 of the chip package structure 1100 have holes 219 a, in accordance with some embodiments. For the sake of simplicity, FIG. 11 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 12 is a top view of a chip package structure 1200, in accordance with some embodiments. For the sake of simplicity, FIG. 12 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 12 , the chip package structure 1200 is similar to the chip package structure 400 of FIG. 4 , except that the shield bump structure 219 of the chip package structure 1200 has a serpentine line, and the main portion of the serpentine line laterally extends across the gap G1 between the chip structures 220A and 220B, in accordance with some embodiments. For the sake of simplicity, FIG. 12 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 13 is a top view of a chip package structure 1300, in accordance with some embodiments. For the sake of simplicity, FIG. 13 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 13 , the chip package structure 1300 is similar to the chip package structure 1200 of FIG. 12 , except that the shield bump structure 219 of the chip package structure 1300 has a serpentine line, and the main portion of the serpentine line extends vertically, in accordance with some embodiments. For the sake of simplicity, FIG. 13 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIG. 14 is a top view of a chip package structure 1400, in accordance with some embodiments. For the sake of simplicity, FIG. 14 does not show the underfill layer and the molding layer, in accordance with some embodiments. As shown in FIG. 14 , the chip package structure 1400 is similar to the chip package structure 400 of FIG. 4 , except that the shield bump structure 219 of the chip package structure 1400 has portions 219P spaced apart from each other, in accordance with some embodiments. The portions 219P have a rectangular shape, in accordance with some embodiments. For the sake of simplicity, FIG. 14 does not show the shield pad 118′, in accordance with some embodiments. In some embodiments, the shield pad 118′ and the shield bump structure 219 have the same shape.

FIGS. 15A-15C are cross-sectional views of various stages of a process for forming a chip package structure, in accordance with some embodiments. As shown in FIG. 15A, the step of FIG. 1C is performed to form the dielectric layer 119 and the seed layer 211 over the dielectric layer 117 and the wiring layer 118 d, in accordance with some embodiments. As shown in FIG. 15A, a mask layer 212C is formed over the seed layer 211, in accordance with some embodiments. The mask layer 212C has an opening 212 b exposing the seed layer 211 thereunder, in accordance with some embodiments.

As shown in FIG. 15A, a conductive layer 1510 is formed in the opening 212 b and over the seed layer 211, in accordance with some embodiments. The conductive layer 1510 is made of a conductive material, such as metal (e.g., titanium, copper, and/or nickel) or alloys thereof (e.g. titanium copper), in accordance with some embodiments. The conductive layer 1510 is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 15B, the mask layer 212C is removed, in accordance with some embodiments. As shown in FIG. 15B, a mask layer 1520 is formed over the seed layer 211, in accordance with some embodiments. The mask layer 1520 has openings 1522 exposing the seed layer 211 thereunder, in accordance with some embodiments. The mask layer 1520 is made of a polymer material, such as a photoresist material, in accordance with some embodiments.

As shown in FIG. 15B, the step of FIGS. 1C and 1D are performed to form the under bump metallization layer 213, the barrier layer 214, the conductive layer 215, and the solder layer 217 a in the openings 1522, in accordance with some embodiments.

As shown in FIG. 15C, the mask layer 1520 is removed, in accordance with some embodiments. As shown in FIG. 15C, the steps of FIGS. 1E-1I are performed to form a chip package structure 1500, in accordance with some embodiments. The shield bump structure 219 includes the conductive layer 1510 and the seed layer 211 thereunder, in accordance with some embodiments.

FIGS. 16A-16C are cross-sectional views of various stages of a process for forming a chip package structure, in accordance with some embodiments. As shown in FIG. 16A, the step of FIG. 1C is performed to form the dielectric layer 119 and the seed layer 211 over the dielectric layer 117 and the wiring layer 118 d, in accordance with some embodiments.

As shown in FIG. 16A, a mask layer 212D is formed over the seed layer 211, in accordance with some embodiments. The mask layer 212D has openings 212 a exposing the seed layer 211 thereunder, in accordance with some embodiments. The mask layer 212D is made of a polymer material, such as a photoresist material, in accordance with some embodiments.

As shown in FIG. 16A, the step of FIGS. 1C and 1D are performed to form the under bump metallization layer 213, the barrier layer 214, the conductive layer 215, and the solder layer 217 a in the openings 212 a, in accordance with some embodiments. As shown in FIG. 16B, the mask layer 212D is removed, in accordance with some embodiments.

As shown in FIG. 16B, a mask layer 1610 is formed over the seed layer 211, the under bump metallization layer 213, the barrier layer 214, the conductive layer 215, and the solder layer 217 a, in accordance with some embodiments. The mask layer 1610 has an opening 1612 exposing the seed layer 211 thereunder, in accordance with some embodiments.

As shown in FIG. 16B, a conductive layer 1610 is formed in the opening 1612 and over the seed layer 211, in accordance with some embodiments. The conductive layer 1610 is made of a conductive material, such as metal (e.g., titanium, copper, nickel, aluminum, or tungsten) or alloys thereof, in accordance with some embodiments. The conductive layer 1610 is formed using a plating process, such as an electroplating process, in accordance with some embodiments.

As shown in FIG. 16C, the mask layer 1610 is removed, in accordance with some embodiments. As shown in FIG. 16C, the steps of FIGS. 1E-1I are performed to form a chip package structure 1600, in accordance with some embodiments. The shield bump structure 219 includes the conductive layer 1610 and the seed layer 211 thereunder, in accordance with some embodiments.

Processes and materials for forming the chip package structures 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500 and 1600 may be similar to, or the same as, those for forming the chip package structure 100 described above.

In accordance with some embodiments, chip package structures and methods for forming the same are provided. The methods (for forming the chip package structure) form a shield bump structure under a gap between two chip structures and over a redistribution structure to prevent the stress concentrated in the gap from damaging wires under the gap.

In accordance with some embodiments, a method for forming a chip package structure is provided. The method includes forming a dielectric layer over a redistribution structure. The redistribution structure includes a dielectric structure and a plurality of wiring layers in or over the dielectric structure. The method includes forming a first conductive bump structure and a shield bump structure over the dielectric layer. The first conductive bump structure is electrically connected to the wiring layers, and the shield bump structure is electrically insulated from the wiring layers. The method includes bonding a first chip structure to the redistribution structure through the first conductive bump structure. The first chip structure is electrically insulated from the shield bump structure, and the first chip structure extends across a first sidewall of the shield bump structure.

In accordance with some embodiments, a method for forming a chip package structure is provided. The method includes forming a shield bump structure over a redistribution structure. The redistribution structure includes a dielectric structure and a plurality of wiring layers in or over the dielectric structure, and the shield bump structure is electrically insulated from the wiring layers. The method includes bonding a first chip structure and a second chip structure to the redistribution structure. The first chip structure and the second chip structure are electrically insulated from the shield bump structure, the first chip structure is spaced apart from the second chip structure by a gap, the shield bump structure extends across the gap from a top view of the first chip structure, the second chip structure, and the shield bump structure, and the shield bump structure is thicker than each wiring layer.

In accordance with some embodiments, a chip package structure is provided. The chip package structure includes a redistribution structure including a dielectric structure and a plurality of wiring layers in or over the dielectric structure. The chip package structure includes a first conductive bump structure over the redistribution structure and electrically connected to the wiring layers. The chip package structure includes a shield bump structure over the redistribution structure and electrically insulated from the wiring layers. The chip package structure includes a first chip structure bonded to the first conductive bump structure. The first chip structure is electrically insulated from the shield bump structure, and the first chip structure partially overlaps the shield bump structure.

The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. 

What is claimed is:
 1. A method for forming a chip package structure, comprising: forming a dielectric layer over a redistribution structure, wherein the redistribution structure comprises a dielectric structure and a plurality of wiring layers in or over the dielectric structure; forming a first conductive bump structure and a shield bump structure over the dielectric layer, wherein the first conductive bump structure is electrically connected to the wiring layers, and the shield bump structure is electrically insulated from the wiring layers; and bonding a first chip structure to the redistribution structure through the first conductive bump structure, wherein the first chip structure is electrically insulated from the shield bump structure, and the first chip structure extends across a first sidewall of the shield bump structure.
 2. The method for forming the chip package structure as claimed in claim 1, wherein a wire of one of the wiring layers extends across a second sidewall of the first chip structure, and the shield bump structure covers a portion of the wire under the second sidewall.
 3. The method for forming the chip package structure as claimed in claim 1, wherein the shield bump structure has at least one hole.
 4. The method for forming the chip package structure as claimed in claim 1, wherein the forming of the first conductive bump structure and the shield bump structure over the dielectric layer comprises: forming a seed layer over the dielectric layer; forming a first mask layer over the seed layer, wherein the first mask layer has a first opening and a second opening exposing portions of the seed layer; forming a conductive layer in the first opening and the second opening; and removing the first mask layer and the seed layer under the first mask layer.
 5. The method for forming the chip package structure as claimed in claim 4, further comprising: forming a solder bump over the first conductive bump structure before bonding the first chip structure to the redistribution structure, wherein the first chip structure is bonded to the solder bump.
 6. The method for forming the chip package structure as claimed in claim 5, wherein the forming of the solder bump over the first conductive bump structure comprises: after forming the conductive layer in the first opening and the second opening and before removing the first mask layer and the seed layer under the first mask layer, forming a second mask layer over the first mask layer and the conductive layer in the second opening, wherein the second mask layer has a third opening over the first opening and exposing the conductive layer in the first opening; forming a solder layer in the third opening; removing the first mask layer, the second mask layer, and the seed layer under the first mask layer; and reflowing the solder layer.
 7. The method for forming the chip package structure as claimed in claim 1, wherein the redistribution structure further comprises a shield pad over the dielectric structure, the shield pad is electrically insulated from the wiring layers and the first chip structure, the first chip structure extends across a second sidewall of the shield pad, and the shield bump structure partially overlaps the shield pad.
 8. The method for forming the chip package structure as claimed in claim 7, wherein a topmost one of the wiring layers is over the dielectric structure, and the shield pad and the topmost one of the wiring layers are made of a same material.
 9. The method for forming the chip package structure as claimed in claim 1, further comprising: forming a second conductive bump structure over the dielectric layer, wherein the second conductive bump structure is electrically connected to the wiring layers; bonding a second chip structure to the redistribution structure through the second conductive bump structure, wherein the second chip structure is electrically insulated from the shield bump structure, the second chip structure extends across a second sidewall of the shield bump structure, the second chip structure is spaced apart from the first chip structure by a gap, and the shield bump structure is under the gap.
 10. The method for forming the chip package structure as claimed in claim 9, wherein the shield bump structure is wider than the gap.
 11. A method for forming a chip package structure, comprising: forming a shield bump structure over a redistribution structure, wherein the redistribution structure comprises a dielectric structure and a plurality of wiring layers in or over the dielectric structure, and the shield bump structure is electrically insulated from the wiring layers; and bonding a first chip structure and a second chip structure to the redistribution structure, wherein the first chip structure and the second chip structure are electrically insulated from the shield bump structure, the first chip structure is spaced apart from the second chip structure by a gap, the shield bump structure extends across the gap from a top view of the first chip structure, the second chip structure, and the shield bump structure, and the shield bump structure is thicker than each wiring layer.
 12. The method for forming the chip package structure as claimed in claim 11, further comprising: forming a shield pad over the dielectric structure before forming the shield bump structure over the redistribution structure, wherein the shield pad is electrically insulated from the wiring layers, the first chip structure, the second chip structure, and the shield bump structure, the shield pad extends across the gap, and the shield bump structure partially overlaps the shield pad; and forming a dielectric layer over the redistribution structure and the shield pad, wherein the shield bump structure is formed over the dielectric layer.
 13. The method for forming the chip package structure as claimed in claim 12, wherein the shield bump structure is thicker than the shield pad.
 14. The method for forming the chip package structure as claimed in claim 12, further comprising: forming a conductive bump structure over the redistribution structure before or after forming the shield bump structure over the redistribution structure, wherein conductive bump structure is electrically connected to the wiring layers.
 15. The method for forming the chip package structure as claimed in claim 11, further comprising: bonding the redistribution structure to a wiring substrate, wherein the shield bump structure is electrically insulated from the wiring substrate.
 16. A chip package structure, comprising: a redistribution structure comprising a dielectric structure and a plurality of wiring layers in or over the dielectric structure; a first conductive bump structure over the redistribution structure and electrically connected to the wiring layers; a shield bump structure over the redistribution structure and electrically insulated from the wiring layers; and a first chip structure bonded to the first conductive bump structure, wherein the first chip structure is electrically insulated from the shield bump structure, and the first chip structure partially overlaps the shield bump structure.
 17. The chip package structure as claimed in claim 16, wherein the redistribution structure further comprises a shield pad over the dielectric structure, the shield pad is electrically insulated from the wiring layers, the first chip structure, and the shield bump structure, and the first chip structure and the shield bump structure both partially overlap the shield pad.
 18. The chip package structure as claimed in claim 17, wherein a portion of the shield bump structure is between the first chip structure and the shield pad.
 19. The chip package structure as claimed in claim 16, further comprising: a second conductive bump structure over the redistribution structure and electrically connected to the wiring layers; and a second chip structure bonded to the second conductive bump structure, wherein the second chip structure is electrically insulated from the shield bump structure, the first chip structure and the second chip structure are spaced apart from each other by a gap, and the shield bump structure extends across the gap.
 20. The chip package structure as claimed in claim 16, wherein the shield bump structure comprises a plurality of portions spaced apart from each other. 